The proposed research is a continuation of a systematic program of inquiry concerned with the basic mechanisms of learning in a sexual behavior system. Sexual behavior has been the focus of extensive research by biologists, psychologists, and other scientists. The study of learning mechanisms also has had a long and distinguished history. Rarely, however, have these two lines of investigation been integrated. A model will be used according to which sexual behavior occurs in response to species typical cues, local cues, and contextual cues. Our previous research has focused on identifying the nature of species typical cues in a sexual behavior system and on demonstrating forms of learning that involve species typical and local cues. The proposed research will broaden the investigation by focusing on the role of the context in which species typical and local cues are encountered, by comparing the conditioning of contextual cues to the conditioning of more focal stimuli in the framework of several important learning variables (the CS-US interval, blocking, and US preexposure), by exploring modulatory learning influences on sexual behavior, by exploring the functional significance of sexually conditioned behavior, and by investigating the hormonal bases of conditioned sexual behavior. The research will provide information about the generality of learning processes, which is critical for the development of theories of learning and for efforts to discover the physiological substrates of learning using simple neural preparations. The research will also provide clues about some of the ways in which learning may contribute to, and be shaped by, natural selection, and begin to provide information about the relationship between sexual learning, sexual motivation, and the performance of conditioned sexual behavior.